Sub-miniature relay



Oct. 15, 1957 D. w. EVERY 2,810,039

SUB-MINIATURE RELAY Filed March 25, 1955 United States Patent SUB-MINIATURE RELAY Donald W. Every, Los Angeles, Calif., assgnor to Hughes Aircraft Company, Culver City, Calif., a corporation of Delaware Application March 25, 1955, Serial No. 496,885

3 Claims. (Cl. 200-93) The present invention relates generally to a relay and relates more particularly to a sub-miniature type relay including means permittingy memory as to the position of operation thereof.

In electromagnetically operated relays, it has become desirable to employ means by which energization thereof may be accomplished by an initial short electrical pulse, with contacts contained within the relay being maintained in a closed condition until another pulse is applied thereto. Additionally, it has also become necessary to employ various relay components in an arrangement enabling disposition in a relatively small space and to provide means whereby the relative positions may accurately be maintained. In electrically or electronically operated devices, as used in Iaircraft and the like, it is important that the space envelope and weight of various components be maintained as small and as light as possible, commensurate with efficient, effective and reliable operation of the device. Accordingly, in order to satisfy these necessities it is imperative that the individual parts of the relay also be light in weight, incorporate multiple functions and be arranged in a manner permitting the most etlicient operating characteristics.

Accordingly, it is one important object of thel present invention to provide a sub-miniature relay including a position memory function.

Another important object of the present invention is to provide a sub-miniature relay having construction features of novelty enabling the disposition of components thereof in an extremely small spaced envelope while still maintaining eicient and reliable operational characteristics.

A further important object of the invention is to provide a sub-miniature relay having means for maintaining various components thereof in relative positions in a manner permitting elimination of complex supporting structure.

A still further object of the invention is to provide a subminiature relay employing electromagnetic means and permanent magnetic means arranged in series in a man- -ner enabling electro-magnetic series aiding or series opposing relationships as between the two magnetic sources.

Still another important object of the invention is to provide a novel sub-miniature relay wherein the components thereof are maintained few in number as compared with like prior arrangements.

Other and further important objects of the present invention will become apparent from the disclosures in the following detailed specification, appended claims and accompanying drawing, wherein:

Figure l is a longitudinal sectional view through the relay of the present invention with portions thereof being shown in elevation;

Fig. 2 is another longitudinal sectional view taken substantially as indicated by line 2-2, Fig. 1;

Fig. 3 is la sectional view similar to Fig. 1 with cornice ponents in different positions and taken substantially as indicated by line 3 3 Fig. 2; and

Fig. 4 is a fragmentary perspective view showing the relationships between certain components of the present relay, with the encapsulation being omitted for clarity.

With reference to the drawing, the sub-miniature relay of the present invention is shown as comprising a lonegitudinaliy disposed electromagnet indicated generally at 10. The electromagnet 10 comprises a coil 11 that is wound on a bobbin 12 that may be made from any suitable non-conductive material such as, for example, plastic or the like. The bobbin 12 has an axially disposed bore 1E therethrough in which a metallic core member 14 is rigidly disposed. One end of the core member 14 extends beyond the bobbin 12, as at 15, and is cut away to present a attened surface 16. The other end of the coil member 14 is disposed in `co-extensive relationship to the complementary end of the bobbin 12 and has a rst conductor 17 secured thereto by means of a riveted portion 18, for example.

The first magnetic conductor 17 extends radially outwardly from the coil member 14, over an end portion of the bobbin 12 and has a portion 20 that is disposed in a plane parallel to and remote from the axis of the coil member 14. This portion 20 of the first conductor 17 is adapted for disposition in contact with one pole (a north pole in the present illustration) of a permanent magnet 2i. The permanent magnet 21 is generally rectangular in cross-section and lies in a plane that is substantially normal to the axis of the coil member 14. The other (south) pole of the permanent magnet 21 is positioned in contact with one end of yan elongated second magnetic conductor 22. The portion 20 of the first conductor and the one end of the second conductor 22 may be secured to the opposite poles of the permanent magnet 21 as by soldering or the like. The conductor 22 eX- tends from the permanent magnet 21 over the exterior surface of the electromagnet 10 and beyond the end thereof remote from the permanent magnet. A generally L-shaped metallic pole piece 23 is -disposed on and in contact with the second conductor 22 in spaced relationship to one end thereof. The pole piece 23 may be secured in position relative to the conductor 22 as by spot welding, soldering or the like. The pole piece 23 has a leg 24 that is disposed normal to the axis of the electromagnet 10, the leg 24 terminating at 25. The surface, defined by the terminus of the leg 24, lies in the plane of the flattened surface 16 of the extension 15 of the core member. A magnetic gap 26 is defined between an axial outer end of the extension 15 and the leg 24.

The end of the second conductor, remote from the permanent magnet 21, has a metallic bushing 27 affixed thereto by means of a screw 23 that threadably engages one end of the bushing. The other end of the bushing 27 is adapted to support a leaf spring member 30, by means of a screw 3l that threadably engages this other end of the bushing. The free end of the leaf spring 30 carries an armature 32 that is adapted to overlie the magnetic gap 26 dened between the core extension 15 and the pole piece leg 24. The armature 32 is normally urged in a direction away from the surfaces 16 and 25 by biasing action of the leaf spring 30, as shown in Fig. l. The free end of the leaf spring 30 has an angularly disposed portion 33 from which is depended a contact 34 of highly conductive material such as silver or the like, the purpose of which will be later described.

As shown primarily in Figs. 2 and 4, a pair of leads 35 and 36 extend from one end of the relay. The lead 35 is adapted to be suitably aihxed, as at 37, to an outer surface of the bushing 27. The lead 36 extends beyond the bushing 27 and has an inner portion 38 bent in sub- 3. Stantiall-y the same direction .asthe pole piece leg- 24, with a surface 40 dened by the end thereof being disposed in the plane of the core extension surface 16 and leg surface 25. The surface 4.0 is adapted for cooperation with the contact member 34, thus toprovide contacts to complete a circuit between the leads 35 and 36, such acircuit extending through the bushing 27 andY leaf spring 30.

The end of the relay remote from the leads 35 and 36 has extending thereto a second pair of leads 41 and 42 that are bent, as indicated at 43, in a direction substantially normal to the axis of the electromagnet 1h. The ends of the leads 41 and 42 have smaller coil leads 44 and 45 affixed thereto which extend to the coil 11 of the electromagnet 10. The leads 41 and 42 may be connected to any suitable source of electrical energy through a switching arrangement 46. All of the leads 35, 36, 41 and 42 are preferably made from highly conductive material, this feature also enabling the use of the end 40 of the lead 36 as one of the contacts for the relay.

As shown in Figs. l through 3, the various components of the present relay are maintained in their respective positions by encapsulation in a molded body 47 of nonconductive material such as, for example, plastic or the like. The material of the body 47 is molded in such a manner as to expose the various surfaces i6, and 40, with an open area 48 defined above these surfaces being closed by means of a cover Si) which may be fused to the body 47 along the junction lines 5l therebetween.

ln operation of the present relay, the armature 32 will initially be in the position shown in Fig. l, thereby leaving the gap 26 open and the contacts 34 and 40 spaced apart. With the relay in this open condition, the residual force of the permanent magnet 21, acting through the core member 14 and first and second conductors, is insuflcient to effect attraction of the armature 32 into contact with the surfaces 16 and 2S. Upon application of current to the coils 11 of the electromagnet it) in a direction to create a magnetic series aiding relationship with respect to the permanent magnet 21, i. e. in such a manner as to create a south pole at the end of the core member 14 adjacent the conductor 17, the armature 32 will he drawn into engagement with the surfaces 16 and 25, thus to close the contacts 34 and 4t) complete an electrical circuit through the leads and 36. lt may be seen .that energization of the electromagnet 10 need only Abe for a relatively short .period of time and that the permanent magnet 21, upon deenergization of the electromagnet 1i), will serve as a memory establishing means to maintain the Varmature in position to retain the contacts 34 and V4() in a closed condition. This closed relationship of the various components is shown in detail in Fig. 3.

In order that the contacts 34 and 4i) may be separated, the switch mechanism 46 may be operated in order that the Acoil 11 ofthe electromagnet 1G may be energized in a .direction, oppositefrom the direction of initial energization, that is in series opposing relationship to the permanent magnet 21. ln this series opposing relationship, Ithe endzof the-core 14 adjacent the permanent magnet 21 will be, in-the present instance, charged as a north pole. The effective magnet force of the electromagnet 10`is only slightly greater than aresidual magnetic force of the permanent magnet 2i, with the force differential therebetween being insufiicient to overcome the force of the leafspring 30 and toimaintain the contacts 34 and `in closed position. Thus, upon such energization of the electromagnet in series opposing relationship to the permanent magnet, the leaf spring 30 will move the armature 32 away from the surfaces 16 and 25, thus to open the contacts 34 and V40 and interrupt the circuit between the leads35and36.

vItmay thus beseen that the present devicehas detail construction-featuresof novelty and that thevarious components arefarranged .in Vsuch a manner as to enable a reduction in the number thereof over and above the number of like components associated with prior like. devices. Additionally, it is to be noted that the arrangement of the components of the present device is such as to enable simplified, easy and rapid assembly thereof with little possibility of failure due to shifting of the parts and/or niisalignment thereof. .n practice, it has been found that the entire relay of the present invention may reliably be constructed in a manner wherein the overall length is less than 3A" with the other dimensions being proportional thereto. This extreme miniatur'ization of components is possible, in part, by the particular arrangement of structural details and the utilization of several components with multiple functions.

Having thus described the invention and the present embodiment thereof, it is desired to emphasize the fact that many modifications may be resorted to in a manner limited only by a just interpretation of the following claims. Y

What is claimed is:

l. A sub-miniature relay comprising, in combination: a non-conductive bobbin; a coil disposed about said bobbin and defining an electromagnet; a metallic core disposed within said bobbin, one end of said core extending beyond one end of said bobbin; a permanent magnet disposed adjacent said electromagnet; a first conductor having one end secured to the other end of said core, the other end of said conductor being positioned in contact with one pole of said permanent magnet; a second con ductor positioned in contact with the other pole of said permanent magnet, said second .conductor extending over an outer surface of said electromagnet; a pole piece carried on said second conductor, said pole piece having a portion lying on the axis of and disposed in spaced relationship to said core thus to define a magnetic gap therebetween; a bushing secured to said second conductor remote from said electromagnet; a leaf spring mounted on said bushing; an armature carried by a free end ,of said leaf spring and adapted to overlie said magnetic gap, said armature being biased in a direction away from said gap by means vof said spring; a contact carried by said leaf spring; and a pair of leads, one of said leads being connected to said bushing, one end of the other of said leads forming a contact adapted for cooperation with said spring carried contact, energization of said clectromagnet in series aiding relationship with said permanent magnet serving to attract said armature in a direction to close said magnetic gap and said contacts, said permanent magnet acting thereafter to maintain the closed condition of said contacts following de-energi- Zation of said electromagnet, energization of said electromagnet in series opposing relationship with said permanent magnet serving to effect separation of said contacts by said leaf spring.

2. A sub-miniature relay comprising, in combination: a non-conductive bobbin; a coildisposed about vsaid bobbin and defining an electromagnet; a metallic core disposed within said bobbin, one end of said core extending beyond one end of said bobbing a permanent magnet disposed adjacent said electromagnet; a first conductor having one end secured to the other end of said core, the other end of said conductor being positioned in Contact with `one pole of said permanent magnet; a second conductor positioned in contact with the other pole of said permanent magnet, said second conductor extending over an outer surface of said electromagnet; a pole piece carried onsaid secondconductor, saidpole piece having a portion lying on the axis of and disposed .in spaced relationship to said core thus to define a magnetic gap therebetween; a bushing secured to said second conductor remote from said electromagnet; a leaf spring mounted on said bushing; an armature carried by a .free endofpsaid leaf spring and adapted to overliesaid magnetic gapbsaid armature being biased in a direction away Y from Vsaidgap by means of said spring; acontact carried by said .leaf spring; a pair of leads, one of said leads being connected to said bushing, one end of the other `of said leads forming a contact adapted for cooperation with said spring carried contact, energization of said electromagnet in series aiding relationship with said permanent magnet serving to attract said armature in a direction to close said magnetic gap and said contacts, said permanent magnet acting thereafter to maintain the closed condition of said contacts following de-energization of said electromagnet, energization of said electromagnet in series opposing relationship with said permanent magnet serving to eifect separation of said contacts by said leaf spring; and a molded non-c-onductive body of plastic material formed about non-movable elements of said relay, closely to confine such elements and to tix the locations thereof.

3. A sub-miniature relay comprising, in combination: a non-conductive bobbin; a coil disposed about said bobbin and defining an electromagnet; a metallic core disposed within said bobbin, one end of said core having a attened portion extending beyond one end of said bobbin; a permanent magnet disposed adjacent said electromagnet, the poles thereof lying in a planenormal to an axis of said bobbing a rst conductor having one end secured to the other end of said core, the other end of said conductor being positioned in contact with one pole of said permanent magnet; a second conductor positioned in contact with the other pole of said permanent magnet, said second conductor extending over an outer surface of said electromagnet; a pole piece carried `on said second conductor, said pole piece having a portion lying on said axis of and disposed in spaced relationship to said core thus t-o dene a magnetic gap therebetween; a metallic bushing secured to said second conductor remote from said electromagnet; `a leaf spring mounted on said bushing; an armature carried by a free end of said leaf spring and adapted to overlie said magnetic gap, said armature being biased in a direction away from said gap by means of said spring; a contact carried by a laterally displaced portion of said leaf spring; a pair of leads, one of said leads being connected to said bushing, one end of the other of said leads forming a contact adapted for cooperation with said spring carried contact, energization of said electromagnet in series aiding relationship with said permanent magnet serving to attract said armature in a direction t-o engage said portions of said pole piece and said core, close said magnetic gap and said contacts, said permanent magnet acting thereafter to maintain the closed condition of said contacts following de-energization of said electromagnet, energization of said electromagnet in series opposing relationship with said permanent magnet serving to effect separation of said contacts by said leaf spring; and a molded non-conductive body of plastic material formed about non-movable elements of said relay, closely to conne such elements and to x the locations thereof.

References Cited in the ile of this patent UNITED STATES PATENTS 2,253,856 Harrison Aug. 26, 1941 2,447,632 Bush Aug. 24, 1948 2,549,323 McMullen et al Apr. 17, 1951 2,632,071 Rinke Mar. 17, 1953 2,702,841 Bernstein Feb. 22, 1955 2,710,365 MacDougall et al. June 7, 1955 

